I just submitted a bug report on this, but thought I would also ask the forum as well.

I just upgraded to After Effects CS6 on a MAC OS X 10.6.8

My probelm is that for certain effects, the RAM preview is not clearing after I make a change. In particular, with "Particle Playground" I have the layer map as another composition. When I make a change to the layer image in its composition, the particle playground composition does not reflect the change and just stays the same.

If I then make another parameter change, the new layer will be there, but if I undo that change it goes back to the old layer map. If I reneder it out to a file it is fine and reflects all changes. However, the preview RAM system seems to be very buggy and very hard to clear out old RAM previews so that changes are reflected in the new preview.

The same thiings happens if I use an expression in particle playground. I change the expression and the preview does not change. Purging doesn't even help. I have been using this effect for some years, so I know what I am doing should not be a problem.

I see others have been having various problems with this new RAM Preview enhancement, which is great when it works, but is almost unworkable in some instances as I have mentioned.

If anyone has solved this problem, or has any ideas that would be great.

It's an "under-the-hood" issue. No fix until the next version of AE or vendors can work around the issue in their own code. You can make things easier by turning off the disk cache, though, as in fact it's a mix-up where the program can't determine the cache state of a frame. No disk cache, less confusion...

Thanks for the reply. At least I know that I am not crazy! I did turn off the disk cache but it didn't help. As you say it might help a bit as with less memory it will refresh sooner although even then sometimes an old frame will remain and nothing short of shutting down AE seems to fix it.

Disabling the disk cache doesn't fix the "RAM Cache" and both are SEVERELY broken on CS6. I can't belieive this build made it to GM.

We've had many instances where changes are made to a "child" comp and the cache from it's parent doesn't get "reset".

Even better we had one occurence where the image drawn from a composition item was not even anything contained AT ALL withing this comp. (but from a different piece of footage)

Purging and disabling the disk cache did not even help in this situation. We had to restart After Effects.

One of the new feature of CS6 was a new caching system ... well they seriously messed it up.

The worst part is that this is a tricky bug to report to Adobe since you can't just send an AE project to them to reproduce the issue since it is random and only affect temporary data "RAM" or disk cache.

CS6 is NOT production ready for the following reasons :

- RAM and Disk Cache is broken

- the new per vertice feather roto tools is UNSTABLE as unstable can be. (unusable for us)

- the multiprocessing engine is unusable, completely broken as-well and will crash on most systems. (even without the use/help of third party plugins)

- the new "cloud" licensing system causes a humongous problem when it comes to license plugins on a render farm.

(they didn't think this through AT ALL)

- the online licensing system is painful to re-activate (if you re-install a machine and forget or can't de-activate it first)

- the cloud licensing system doesn't support a "group" or "business" accounts where you can get multiple subscriptions on the same account (they're working on it now apprentely)

Thanks for your lengthy reply. I have experienced at least half of the problems you mentioned already. What I do now before I run RAM preview is make a change to a dummy parameter that has no effect on the comp;osition, but works to clear the memory. It is an extra step, but from what I can tell, it does render faster so I guess I will live with it until things improve - sooner rather than later I hope!

We're still getting this issue on 3 machines running AE CS6, even after running the update (11.0.2.11 currently). The only thing that seems to solve it is disabling disk cache and then running the 'Throttle-n-purge' script to clear the RAM preview. Old frames showing up randomly throughout a render is very annoying.